TVOCs

The following table was developed using available literature, data from numerous companies and Industrial Hygienists active in the IAQ field together with empirical data from many personal investigations.  It provides a workable definition of the limits and effects of C3‑C15 TVOC concentrations and has proven to be a good predictor of the level of expected symptoms of non-chemically sensitive people.

Total VOCs in the Air

Home Office

 

Level  ng/L (µg/M3) Level  ng/L (µg/M3)

Meaning

Less than 200 Less than 200 Ideal
200-300 200-350 Good
300-400 350-500 Acceptable
400-500 500-700 Marginal
More than 500 More than 700 Poor; the higher the number, the worse the problem

 

Production/Manufacturing

 

Level  ng/L (µg/M3)

Meaning

Less than 500 Ideal
500-700 Good
700-1000 Acceptable
1000-1500 Marginal
More than 1500 Poor; employee complaints probable; the higher the number, the worse the problem
1500-3000 Exposure effects possible
3000-25000 Exposure effects probable
More than 25000 Toxic range, potential neurological effects

 The next step in understanding VOCs is to consider collections of compounds that give indications of the five most common VOC problems:  gasoline, paint, odorants, personal care, and lifestyle.

Gasoline has six “marker compounds” associated with it.  They are benzene, toluene, ethylbenzene, and the three xylene isomers.  The source of gasoline can be ambient air (especially in urban environments) but it is generally the office occupants themselves who supply the contamination.  Remember that for every gallon of gas pumped into an automobile, one gallon of air saturated with gasoline vapor is dumped into the lap of the person filling the tank.  This person then goes to the office or home and off gasses the rest of the day.  The gasoline levels in homes are generally higher than in offices because, in addition to the personal off gassing, the most common source of gasoline vapors is the collection of gas cans, mowers, trimmers, etc. in the attached garage.

Paints are very complex and can have several different markers but typically they include methylcyclohexane, substituted cyclics, butylcellosolve, substituted alcohols, unsaturated C9-C12 hydrocarbons, and the straight-chain hydrocarbons nonane (C9) through dodecane (C12).  Paint VOCs can linger at significant levels for as long as 18 months after application; however, even though the paint may be fully cured, leaking paint cans often contribute to the VOC load for years.

Odorants are chemicals that are supposed to smell good.  They are in air fresheners, potpourri, scented oils, perfumes/colognes, and nearly all cleaning and personal care products.  In a typical office, especially in an office or home where an IAQ problem exists that the occupants think they can eliminate by covering it up, odorants can make up a significant fraction of the TVOC load.  These odorants include many aldehydes, alcohols, ketones, pinenes, and complex esters.

Personal care products are the primary source of acetone.  Acetone is typically associated with nail care (nail polish remover is nearly 100% acetone).  Other compounds associated with personal care include the C2-C5 acetates (nail care), isopropanol, and ethanol (cosmetics and hair spray), and menthol, camphor, and methylsalicylate (topical ointments).

 Lifestyle chemicals are many and varied but the three primary compounds are ethanol from antiseptic wipes (although the occasional leaking bottle of scotch cannot be ruled out), tetrachloroethylene or PCE, from garments that have been dry cleaned, and 1,4-dichlorobenzene from mothballs.

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